Drill jig



Nov. 26, 1946.

c. H.l COLE DRILL JIG Filed June 28, 1944 W/lW//AW/Amm INVENTOR.

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AT TURNEYS Patented Nov. 26, 1946 U N IT ED 'STATES 'PAT ENT OFFICE DRILL JIG Charles H. Cole, Leonia,.N.'J. ApplicationJ une 28, 1944,. Seral.No..542,486

.6 Claims.

1 This'invention relates to a drill jig or template, and particularly' to such a device which isv adapted to facilitate the quick and accurate measurement 'of distances, as between centers of' holes to be drilled in a Work piece.

An object ofthe invention is to provide a device which can be used, without adjustment of any moving part,v to measure a wide variety of distances in small steps betweena minimum and a maximum.

Another object is to provide such a device which is simple and inexpensive tomanufacture and is durable, accurate and easy to use.

A further object is to' provide certain improvements in the form, construction and arrangement of the device whereby the above-named and other objects may effectively be attained.

A practical embodiment of the invention is shown in the accompanying drawing, in which Fig. l represents a top plan view ofthe jig;

Fig. 2 represents a side elevation of the jig; and y Fig. 3 represents a transverse section taken along the line III-III of Fig. 1.

Referring'to the drawing, the jig shovvn'there-- 'in comprises'a fiat rectangular plate, preferably of a hard metal such as tool steel, hardened and ground so that its opposite surfaces are parallel and flat. This plate has drilled therein a plurality of rows of small holes, the rows being designated by the letters A, B, C,'D and E, and the holesin each row being numbered sequentially for ready reference; the letters and numbers shown being stamped or otherwise applied to the surface of the plate. uniform in sizeV and are drilled accurately so that their axes are perpendicular to the surface of the plate' and their centers spaced predetermined distances apart.

could be reduced, for instance to ii the jig is to be used only for drafting and layout work, while the full'thickness is desirable when machine The holes are preferablyI In the jig shown the plate is* 2" X4, with a thickness of T"e; this thicknessY shop use (drill centering, etc.) is contemplated. lThe'holes l-3I in row A arespaced .1250 on centers, this ro-w extending parallel to the long side ofthe plate. Row B starts with a hole B-I, which is '..1250 from hole A-l in a direction .parallelto the short end ofthe plate, and continues .with holes spacedincreasing distances vfrom-.the correspondingly numbered holesl in row Auntil hole B-3l isl reached Aat a distance of .5938 from=hole A-3l. Rows C` and D lie parallel to row B, row 4C being .4844 from row Bl and row D being thesame rdistance beyond row C, .measured horizontally. Row E is correspond- VVingly disposed but .comprises onlytwelve. holes.

,From-fthe foregoing it will be seen that distances in multi-ples of..1250" vcan bemeasured by the use of row A alone, from .1250 upto 3.7500". Distances from the same. minimum up to 1.7500" in stepsof .0156-jcan be measured by taking holes 4in Vrovi/2A and'` like numbered'holes in` rows B, C, D or E; while longerdistances up Yto 4.0808 ll-A3 i) canbe measured along diagonals.V It is further provided that additional holes Such .as those marked F andV G maybe drilled .inthe plateat points which will permit I.the measurement of Adistances not accurately measurable .between .pairs of 'holes in the regularly disposed rows (Ato E. Since accuracy to four decimal .places is normally sufficient, vthe arrangement shown is suitable for use within the limits indicated. The dimensions named'arefnot intended .to-be criticaL'but-rather togexemplify one form of the jig .While 4other forms would include spacing .'of the holes. inrow A at distances of 116 vor m 'metric distances, the lother rows being corretspondinglytmodi'ed. The: jigxisvintended to `belused'in connection with' a reference table having distancesv arranged linregular .sequence opposite notations of the hclesto :be used.' inmeasurement of such l"dis- '^tances,.fas' Vfollows:

Distance table Dist. Holes Dist. Holes Dist. Holes Dist. Holes 1250 1x1-A1 .6094 01-.41 1. 093s D1-A1 1. 5781 111-141 1406 132-42 .6250 02-142 1. 1094 i12-A2 1. 593s i12-A2 1562 -Bs-As .6406 03-.43 1. 1250 13a-.43 1, 6094 11a-A3 1719 134-114 .6563 04-.44 1. 1406 134-44 1. 6250 114-144 1757 :B1-A2 .6719 05-.45 *1. 1547 G-A 16 1. 6406 E5-A5 1875 B5-.45 .6575 06-46 1. 1563 D5-A5 1. 6563 116-146 1381 Bz- 7031 07-147 1. 1719 D13-.46 1. 6719 E7-A7 2000 :B3-i s. 7071 F-AZO 1. 1875 D7--A7 1. 6875 EB--AS Dist. Holes Dist. Holes Dist. Holes Dist. Holes .5000 B25-A25 9767 C24-ggg 1. 465s B25-A25 5001 B24-gi 0544 C25-A25 1. 4531 D24-A24 .5313 B27-A27 1.0156 027-1127 1.5000 f B27-A27 .5469 B25-.42s 1.0313 C25-.42s 1.5156 B2S-A28 5781 B30-.430 1. 0625 C30-A30 1. 5469 D30-A30 In the foregoing table the distances marked parallel to said second-named row and having are interpolated into the regular sequence, as for instance to meet the special requirements of a particular user, and other such distances 4may readily be calculated (trigonometrically or otherwise) and indicated as desired.

In a like manner, the jig may be used, in conjunction with a suitable table, to measure and lay out angles, Yone hole'corresponding to the lapex of the angle while the sides are located by selecting holes'which correspond to points thereon. Such a table may include the following ndications, given by way of example:

Angle table 432 I A1-E1-A2 291 Al-El-AS 4F38 A2-B2-A3 8152 Al-Bl-AS The jig is used on machine work by passing a close-htting drill or punch through the selected holes in order to mark, for instance, the centers for a further drilling operation; while in drafting work a pencil or other pointed device may be used for marking desired centers or other points.

It will be understood that various changes may be made in the form, construction and arrangement of the device without departing from the -spiritand scope of the invention,` and hence I do not intend to be limited to the details herein `shown and described, except as they may be inits holes disposed in the same manner.

2. A device according to claim l in which the 'distance between the farthest spaced corresponding holes in said rst and second-named rows is less than the distance between the nearest spaced corresponding holes in the rst-named row and the nearest additional row.

3. A device of the character described comprising a at rectangular plate provided with a straight row of equally spaced holes of substantially equal diameters parallel to a side oi the plate, and a plurality of additional rows of equally spaced holes parallel to each other and forming the same angle with the line of the first-named row, corresponding holes in the several rows being equally spaced from the ends of the plate.

e. A device according to claim 3 in which the difference in distances between any two adjacent holes in the first-named row and corresponding adjacent holes in any other row is the same as the diierence in distances between any other two pairs of corresponding adjacent holes.

5. A device according to claim 3 in which the distance between the farthest spaced corresponding holes in the rst-named row and any row other than the most distant row is less than the distance between the nearest spaced corresponding holes in the first-named row and the row next beyond the row to which said rst-mentioned distance is measured.

6. A device according to claim 3 in which the distance between the farthest spaced corresponding holes in the first-named row and any row other than the most distant row is less than the distance between the nearest spaced corresponding holes in the first-named row and the row next beyond the row to which said rst-mentioned distance is measured, the difference in said distances being the same as the difference in distances between adjacent holes in the first-named row and corresponding adjacent holes in any other row.

CHARLES H. COLE. 

